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International Journal of Computational Engineering Research||Vol, 03||Issue, 5||
Pulsed Electrodeposition of Nano-Crystalline Ni with Uniform
Co-Depostion of Micron Sized Diamond Particles on Annealed
Copper Substrate
Prashant Kumar 1 , Neelima Mahato 2 , Vandana Singh 2 , Raja Chaudhary 2 ,
Kantesh Balani 2
1 Department of Metallurgical Engineering
Indian Institute of Technology, Banaras Hindu University, Varanasi- 221 005
2 Materials Science and Engineering, Indian Institute of Technology, Kanpur- 208 016
ABSTRACT
Nanocrystalline nickel was deposited on annealed copper substrate of unit surface area (1
cm 2 ) via pulsed electrodeposition technique using potentiostat (model 263A, Princeton Applied
Research, USA) from Watts bath containing nickel sulfate, nickel chloride , boric acid and sodium
citrate. Diamond particles of three different dimensions, viz., 1, 3, and 6 micron were added
separately (5 g/L) to the watts bath and co-deposited along with nanocrystalline nickel. The
temperature was kept constant at 55 °C. The solution was sonicated for 45-60 minutes prior to
deposition to disperse the diamond particles uniformly in the bath. Depositions were carried out at
different current densities, viz., 50, 100 and 200 mA/ cm 2 for different durations, i.e., 7, 14 and 21
minutes and best results are optimized for 200mA/cm 2 so it is used for all process here .Scanning
electron micrographs(SEM) show uniform deposition of Microstructure of micron diamond on the
surface of copper embedded in the nickel matrix. Elemental mapping confirmed uniform deposition
of nickel and diamond with almost no cracks or pits. Mechanical properties such as, Vicker’s
hardness and wear properties were investigated using microindentation, tribology and laser
profilometry. Improved microstructural and mechanical properties were found in the case of
electrodeposited surfaces containing followed by 3 and 6 micron diamond. The properties were also
found better than those processed via stirring the solution during deposition.
KEYWORDS: Nanocrystalline Ni, Electrodeposition, Codeposition, Annealed copper.
I. INTRODUCTION
In the current work, nanocrystalline Ni-Diamond films were synthesized by pulsed electrodeposition
using a watts bath . Depositions were optimized on the current density range of 50-200 mA/cm 2 and
200mA/cm 2 was best suitedto achieve a uniform equiaxed coating with a target of high Ni-Diamond content
owing to their superior corrosion resistance and enhanced hardness. Nowadays, in order to fabricate
nanocrystalline metallic films, many deposition techniques are available, such as sputtering, molecular beam
epitaxy, vacuum evaporation, sol-gel, thermal spray, etc. But all these methods require high precision process
control, which demand higher capital cost and incur huge material waste. But electrodeposition is an established
and inexpensive technology among other fabricating processes which is accomplished by fabricating metallic
alloys using low-temperature synthesis from aqueous solutions. This has an advantage of preparation of films
over a large surface area without impairing materials purity in a relatively shorter period of time. In the
electrodeposition process, the film properties mainly depend on deposition conditions, e.g, current density,
deposition potential, bath type density, deposition potential, bath type density, deposition potential, bath type
the electrochemical deposition conditions as well as physical parameters such as thickness, the substrate type,
and orientation, it is possible to control and optimize the electrodeposited films (such as coating thickness,
cluster size, etc.)
Nanosized Ni deposits require the application of much higher current densities, which normally leads
to cracks in films. Pulse electro deposition provides more uniform and crack-free deposits with required
properties. The pulse electrodeposited Nanocrystalline (nc) Ni-Diamond films can receive great attention due to
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